Question

In: Civil Engineering

Explain functioning and importance of ACTIVATED SLUDGE PROCESS in Sewage Treatment. What factors adversely affect overall...

Explain functioning and importance of ACTIVATED SLUDGE PROCESS in Sewage Treatment. What factors adversely affect overall performance of Treatment?

Expert Solution

ACTIVATED SLUDGE PROCESS

Functioning

Activated sludge process is one of the biological secondary treatment processes.

Activated sludge contains aerobic micro organisms which oxidizes organic matter in the sewage.

It consists of an aeration tank and a clarifier.

The sewage is mixed with activated sludge in the aeration tank and it is aerated for a period of time. The it is allowed to settle in the clarifier. The activated sluge along with the oxidized organic matter settle down and the rest is discharged as effluent. The settled sludge is either disposed as waste or it can be reused.

Importance

Activated sludge process can be used for removing

1. Carbonaceous matter

2. Nitrogenous matter

3. Phosphate

4. gases like CO2, NH3, Nitrogen, etc

It removes seasonal problems like statification, algae growth, etc.
Removes odor
Eliminate aerosol generation

factors adversely affecting overall performance of Treatment

1. pH

2. Temperature

3. Electrical conductivity

4. Total dissolved solids

5. Nitrates, Chlorides and Sulphates

6. Total coliform removal efficiency

Ally Wells answered 8 months ago

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